X-Git-Url: https://wimlib.net/git/?a=blobdiff_plain;f=include%2Fwimlib%2Fdecompress_common.h;h=5d7c4e5abb441ce5e3fe625869c673d1a4b4b234;hb=0ae7e5538476723feb14f07a478b92210e24a21b;hp=6762043c8b0ab30081c51b83454fd76820d27ecb;hpb=0ecb0529b5fcacc1abafa1f3f02a40c44783ada8;p=wimlib

diff --git a/include/wimlib/decompress_common.h b/include/wimlib/decompress_common.h
index 6762043c..5d7c4e5a 100644
--- a/include/wimlib/decompress_common.h
+++ b/include/wimlib/decompress_common.h
@@ -10,9 +10,9 @@
 #ifndef _WIMLIB_DECOMPRESS_COMMON_H
 #define _WIMLIB_DECOMPRESS_COMMON_H
 
-#include "wimlib/assert.h"
+#include <string.h>
+
 #include "wimlib/compiler.h"
-#include "wimlib/endianness.h"
 #include "wimlib/types.h"
 #include "wimlib/unaligned.h"
 
@@ -60,7 +60,6 @@ static inline void
 bitstream_ensure_bits(struct input_bitstream *is, const unsigned num_bits)
 {
 	/* This currently works for at most 17 bits.  */
-	wimlib_assert2(num_bits <= 17);
 
 	if (is->bitsleft >= num_bits)
 		return;
@@ -93,9 +92,7 @@ overflow:
 static inline u32
 bitstream_peek_bits(const struct input_bitstream *is, const unsigned num_bits)
 {
-	if (unlikely(num_bits == 0))
-		return 0;
-	return is->bitbuf >> (32 - num_bits);
+	return (is->bitbuf >> 1) >> (sizeof(is->bitbuf) * 8 - num_bits - 1);
 }
 
 /* Remove @num_bits from the bitstream.  There must be at least @num_bits
@@ -162,18 +159,17 @@ bitstream_read_u32(struct input_bitstream *is)
 	return v;
 }
 
-/* Read an array of literal bytes embedded in the bitstream.  Return a pointer
- * to the resulting array, or NULL if the read overflows the input buffer.  */
-static inline const u8 *
-bitstream_read_bytes(struct input_bitstream *is, size_t count)
+/* Read into @dst_buffer an array of literal bytes embedded in the bitstream.
+ * Return either a pointer to the byte past the last written, or NULL if the
+ * read overflows the input buffer.  */
+static inline void *
+bitstream_read_bytes(struct input_bitstream *is, void *dst_buffer, size_t count)
 {
-	const u8 *p;
-
 	if (unlikely(is->end - is->next < count))
 		return NULL;
-	p = is->next;
+	memcpy(dst_buffer, is->next, count);
 	is->next += count;
-	return p;
+	return (u8 *)dst_buffer + count;
 }
 
 /* Align the input bitstream on a coding-unit boundary.  */
@@ -215,9 +211,9 @@ bitstream_align(struct input_bitstream *is)
  * input data is exhausted, the Huffman symbol is decoded as if the missing bits
  * are all zeroes.
  *
- * XXX: This is mostly duplicated in lzms_huffman_decode_symbol() in
- * lzms-decompress.c.  */
-static inline u16
+ * XXX: This is mostly duplicated in lzms_decode_huffman_symbol() in
+ * lzms_decompress.c.  */
+static inline unsigned
 read_huffsym(struct input_bitstream *istream, const u16 decode_table[],
 	     unsigned table_bits, unsigned max_codeword_len)
 {
@@ -254,6 +250,25 @@ make_huffman_decode_table(u16 decode_table[], unsigned num_syms,
 			  unsigned num_bits, const u8 lens[],
 			  unsigned max_codeword_len);
 
+static inline void
+copy_word_unaligned(const void *src, void *dst)
+{
+	store_word_unaligned(load_word_unaligned(src), dst);
+}
+
+static inline machine_word_t
+repeat_byte(u8 b)
+{
+	machine_word_t v;
+
+	STATIC_ASSERT(WORDSIZE == 4 || WORDSIZE == 8);
+
+	v = b;
+	v |= v << 8;
+	v |= v << 16;
+	v |= v << ((WORDSIZE == 8) ? 32 : 0);
+	return v;
+}
 
 /*
  * Copy an LZ77 match at (dst - offset) to dst.